Water swollen cellulose and blends dyed with insoluble, non-vattable anthraquinone dyes in a glycol ether solution

ABSTRACT

WATER SWELLABLE CELLULOSIC FIBERS, FOR EXAMPLE, COTTON, OR BLENDS OR MIXTURES THEREOF WITH SYNTHETIC FIBERS, FOR EXAMPLE, POLYESTER FIBERS, UNIFORMLY DYED TO BLUE TO GREEN SHADES WITH ESSENTIALLY WATER INSOLUBLE, NON-VATTABLE, 1AROYLAMINO-5,8-DI(N-SUBSTITUTED)AMINOANTHRAQUINONE DYES, FOR EXAMPLE, 1-BENZOLYAMINO-5,8-BIS(P-TOLUIDINO) ANTHRAQUINONE, SAID DYED FIBERS BEING FAST TO WASHING, DRYCLEANING AND SUBLIMATION AND EXHIBITING A REFLECTANCE COLOR VALUE (S&#39;&#39;) AFTER SCOUR OF AT LEAST ABOUT 2.

United States Patent 3,752,645 WATER SWOLLEN CELLULOSE AND BLENDS DYEDWITH lNSO-LUBLE, NON-VATTABLE A'NTHRAQUINONE DYES IN A GLYCOL ETHERSOLUTION Thomas Michael McGuire, Newark, Del., assignor to g. du Pont deNemours and (Iompany, Wilmington,

e N0 Drawing. Filed July 30, 1971, Ser. No. 167,830

Int. Cl. C0911 /62; 1306p 3/82 U.S. Cl. 8-21 C Claims ABSTRACT OF THEDISCLOSURE Water swellable cellulosic fibers, for example, cotton, orblends or mixtures thereof with synthetic fibers, for example, polyesterfibers, uniformly dyed to blue to green shades with essentially Waterinsoluble, non-vattable, 1- aroylamino 5,8di(N-substituted)aminoanthraquinone dyes, for example,1-benzoylamino-5,8-bis(p-toluidino) anthraquinone, said dyed fibersbeing fast to washing, drycleaning and sublimation and exhibiting areflectance color value (5') after scour of at least about 2.

BACKGROUND OF THE INVENTION (1) Field of the invention This inventionrelates to uniformly dyed Water swellable cellulosic fibers and to dyedmixtures or blends of such water swellable cellulosic fibers andsynthetic fibers.

(2) Description of the prior art It is well known in the art thatsynthetic fibers, for example, fibers prepared from polyesters,polyamides or cellulose acetate, can be dyed with a wide variety ofdisperse dyes whose solubilities in water vary from very low tomoderately high.

Natural fibers such as water swellable cellulosic fibers, especiallycotton, are dyed by processes, and with dyes, which usually differmarkedly from the processes and dyes employed with synthetic fibers. Theconventional methods for dyeing water swellable cellulosic materials maybe summarized as follows:

1) A high molecular weight water insoluble dye is formed within thematerial, either by reacting two smaller components, as in the formationof an azoic dye by a coupling reaction, or by a chemical reaction whichrenders insoluble a soluble dye precursor, as in vat and mordant dyeing.

(2) A water soluble preformed dye having an alfinity for the cellulosicmaterial is exhausted onto the material from an aqueous solution by aprocedure which involves reducing the solubility of the dye in theaqueous solution, as with direct dyes.

(3) A dye containing a substituent which reacts with the cellulose or amodified cellulose is exhausted onto the material from either an aqueousor non-aqueous solution under conditions such that the dye is chemicallybonded to the substrate, as with fiber reactive dyes.

(4) Water insoluble pigments are bonded to the cellulose with polymericmaterials, as in pigment printing.

(5) A finely divided form of a Water insoluble dye is incorporated intothe cellulose during a manufacturing step, as is sometimes done duringspinning of viscose rayon.

None of those conventional procedures can be used to dye water swellablecellulose by directly introducing into the material a preformed,nonreactive, water insoluble dye since such dyes have little naturalaffinity for or substantivity to such cellulosic materials.

Representative of the aforesaid processes wherein dyes are formed insitu after a precursor is deposited on or within the cellulose areprocesses disclosed in U.S. Pats. 396,692 and 2,069,215 and British Pat.1,071,074. A process employing water soluble preformed dyes for dyeingcellulose is discussed in the Journal of the Society of Dyers andColourists, 73, 23 1957).

The aforesaid processes suffer from a variety of disadvantages, such ascomplexity of application, inability to achieve a broad spectrum ofcolors, and low fastness of the dyed cellulose to aqueous washing and/ordrycleaning with organic solvents.

The use of dyes of low water solubility for dyeing cotton is disclosedin British Pat. 1,112,279. The process involves the application of dye,water and urea or a structurally related compound to the substrate,followed by heating. In such a process dye utilization frequently ispoor and undesirable basic degradation products from the urea or relatedcompound may be formed.

Problems in addition to the above are encountered in the use of priorart dyes and dyeing processes for blends or mixtures of water swellablecellulosic and synthetic materials. Generally, complex two-stageprocesses are required and the components of the blend or mixture aredyed in separate steps with different dyes. Cross-staining may resultand the amounts of dyes required usually are high, with each componentundesirably interfering With the dyeing of the other. Whencross-staining occurs, the dye must be capable of being scoured oil thestained component. Even under optimum conditions, however, shade matchon both components of the blend is difficult to achieve. The complexityof the two-stage process for dyeing blends also is apparent from aconsideration of the divergency of operating conditions betweenconventional dyeing processes for water swellable cellulosic materialsand synthetic materials. In contrast to the aforesaid procedures fordyeing water swellable cellulose, the usual procedures for dyeingsynthetic materials are based on dissolution of water insoluble dyes inthe synthetic material.

Representative of prior art on the dyeing of blends of such cellulosicand synthetic materials employing a twostage process is U.S. Pat.3,313,590. Analogous to the dyeing of such blends and confirming theaforesaid distinction between Water swellable cellulosic materials andnon-water swellable cellulose acetate, U.S. Pat. 3,153,563 discloses atwo-stage process wherein the cellulose acetate is dyed with a waterinsoluble dye Without coloring the cellulose which then is dyed in anindependent step.

The swelling of cotton fibers and other similar cellulosic materials bywater has long been known. Swelling usually is rapid upon contact withWater, but it is facilitated by Wetting agents and by heat. The swollenmaterials are enlarged, more flexible, reduced in strength, andotherwise modified in physical and mechanical properties. Because oftheir open structure, swollen cellulosic materials can be penetrated byand reacted with low molecular weight water soluble compounds. Valko andLimdi in Textile Research Journal, 32, 331-I337 (1962) report thatcotton can be swollen with water containing both high boiling. watersoluble, non-reactive compounds of limited molecular weight and acrosslinking agent. The Water can be removed with retention of swellingand crosslinking can then be effected. The authors suggest that thetechnique may be useful not only for the introduction into cotton ofwater soluble reactive materials (crosslinking agents) but also otherreactive materials which are insoluble in water but soluble in said highboiling, Water soluble, nonreactive compound. A similar technique isdescribed in U.S. Pat. 2,339,913 issued Jan. 25, 1944 to Hanford andHolmes. The cellulosic is swollen with water, the water then is replacedwith methanol-benzene and finally with benzene, with. retention ofswelling. A cellulose-reactive material (crosslinking agent) is added asa benzene solution and crosslinking is effected.

Blackwell, Gumprecht and Starn in Canadian Pat. 832,343 disclose aprocess for dyeing water swellable cellulosic materials with preformeddisperse dyes, that is, 5 dyes which do not require an in situ chemicalreaction, such as oxidation or reduction, for development of color onthe substrate, such as a fabric, which process comprises contacting thewater swellable cellulosic material in any sequence with the following:

1) Water in an amount sufficient to swell the cellulose;

(2) A preformed dye in an amount sutficient to color the cellulose, aboiling saturated solution of which dye in 0.1 molar aqueous sodiumcarbonate exhibits an optical absorbance not in excess of about 30; and

(3) A solvent in an amount sufiicient to maintain swelling of thecellulose if water is removed, and which n is or 1;

m is a positive whole number;

O 35 wherein R is C alkyl, C cycloalkyl, C aralkyl or alkaryl, C aryl, Caryl, or furfuryl; R is -OH, OR SR NRI-I -NR (C alkyl), -NR (C aralkylor alkaryl),

--0( ?R -0 s 02m, 0 JoR -NH(phenyl), or NH(naphthyl), wherein R is asdefined above;

x is the number of unsatisfied valencies in A; and

in which y is 2, 3 or 4; z is 0,1, 2, 3 or 4 but no greater than y; andR is as defined above; provided that at some stage during the processthe interior of the swollen cellulose is contacted with a solution ofthe preformed dye in aqueous solvent or solvent.

Particular embodiments of the aforesaid process include those whereinsaid solution is formed within and/ or outside the swollen cellulose andthose wherein solution of dye in aqueous dye solvent or dye solvent isachieved by means of heat, by reducing the proportion of water to dyesolvent, or by adding an auxiliary solvent. Embodiments of the processalso include dyeing at elevated temperatures.

Still other embodiments of the aforesaid process include the dyeing ofblends or mixtures of cellulosic and synthetic materials, such aspolyamide or polyester, with the same dye. In such a process thecellulose is dyed as described above and the synthetic material is dyedeither at the same time or in an independent step of the process.

British Pat. 1,147,110 discloses sulfonated, water soluble, fiberreactive anthraquinone dyes. Page 6 of said 75 patent broadly disclosesa method for preparing intermediates for such fiber reactive dyes, whichintermediates include compounds having the formula RNH 0 wherein R isaryl.

OBJECTS AND SUMMARY OF THE INVENTION It is an object of the presentinvention to provide uniformly dyed fibers. A further object is toprovide uniformly dyed water swellable cellulosic fibers and uniformlydyed blends or mixtures of water swellable cellulosic fibers andsynthetic fibers. Still another object is to provide uniformly dyed blueto green fibers which are fast to washing, drycleaning and sublimationand which exhibit a reflectance color value (5) after scour of at leastabout 2. Another object is to provide water swellable cellulosic fiberswhich have been dyed with essentially water insoluble, non-vattableanthraquinone dyes.

The present invention resides in uniformly dyed blue to green waterswellable cellulosic fibers or blends or mixtures of water swellablecellulosic fibers and synthetic fibers, said dyed fibers being fast towashing, drycleaning and sublimation and exhibiting a reflectance colorvalue (8) of at least about 2 after one thorough scour in aqueousdetergent at -l00 C. and one thorough scour in perchloroethylene at 50C., wherein said dyed fibers the dye comprises the anthraquinone dyehaving the formula X oI NH-CO-R;

I ll X 0 wherein R is C alkyl, naphthyl, phenyl or phenyl substitutedwith C alkyl, C alkoxy, Cl, Br, C1 or N0 and X contains 6-18 carbonatoms and is NHalkyl, NHcyclohexyl, N(alkyl) or NHR wherein R is a 0 t bwherein a is H, alkyl or alkoxy, -b is H, alkyl, alkoxy, F, Cl, Br,NHCOalkyl or NHCOR, and c is H, alkyl, alkoxy, F, Cl, Br, NHCOalkyl,

NHCOR, R, OR, NHR, CF CN, CONH CONH- alkyl, CON(alkyl) CONHR,CON(alkyl)R, SO NH SO NHalkyl, SO NHR, SO N(alkyl) SO N(-alkyl)R,COalkyl, COR, CO alkyl, CO R, SO alkyl, 50 R or N=NR, wherein R isphenyl or phenyl substituted with alkyl,

alkoxy, halogen, CF or N0 provided that the 6-position of R issubstituted with H, or if the 2-position is substituted with Br or alkylof greater than two carbon atoms, then H or Br, or if the 2-position issubstituted with C alkyl, then H, Br or C alkyl.

DETAILED DESCRIPTION OF THE INVENTION The aforesaid anthraquinone dyeswhich are used in the preparation of the dyed fibers of this inventionare prepared by conventional processes and techniques. As an example ofsuch processes and techniques, an aliphatic amine, such as listed inTable 1, or an aromatic amine, such as listed in Table 2, can becondensed with S-aminoquinizarin or 1,4,5-triaminoanthraquinone. Bothare prior are known compounds. The reaction is carried out by reducingeither of the aforementioned anthraquinone derivatives wholly orpartially to the leuco form in known fashion and heating the resultingmaterial with at least two moles of the amine in a suitable solvent.With aryl amines, the reaction is carried out in the presence of boricacid. Suitable solvents include chlorobenzene, Cellosolve, l-pentanoland an excess of the amine itself. Zinc and hydrochloric acid can beused as the reducing agent by adding these materials directly to thereaction mixture. Alkyl amines can be condensed with S-aminoquiniZarinor 1,4,5-triaminoanthraquinone in aqueous alcoholic media in thepresence of sodium carbonate or sodium hydroxide. Sodium hydrosulfitecan be used as the reducing agent in these systems. The leuco form ofthe product is then oxidized in each case by prolonged heating of thereaction mixture in air, advantageously in the presence of an aromaticnitro compound.

TABLE 1 n-Hexy1arnine n-Dodecylamine Di-n-hexylamine Di-n-nonylamine nOctadecylamine Cyclohexylamine Di-n-propylamine 4-n-octylcyclohexylammeTABLE 2 Aniline 2,3-2,4-, 2,5- or 3,5-dichloroaniline2'chl0ro-5-trifiuoromethylaniline 2-chlor0-4methylaniline2-chloro'5-methylaniline 3-ch10r0-2-methylaniline3-chloro-4-rnethylam'line 4-chloro-2-2-methylaniline5-chloro-2-methylaniline 2-chloro-5-methoxyaniline5-chloro-2-methoxyaniline 4-fiuoro-2-methylaniline5-fiuoro-2-rnethylaniline 4-chloro 2,B-dimethoxyanilinep-Aminoacetophenone p-Octylsulfonylaniline m-Aminobenzoic acid, propylester p-Amiobenzophenone 4amino 3-br0mobenzophenone4-amino-4-nitrobenzophenone p-Annnobenzoic acid, 1)-

chlorophenyl ester 4-(p-butoxyphenylsulfonyD- S-cthylaniline2,fi-dimethoxy--(phenylsulfonyD- aniline p-(Phenylazo) aniline4-(p-nitrophenylazo)-2-methoxyb-methylaniline2-toluidine-4-(N-butylsulfonamide) 2-anisidine-5-(N,N-dimethy1-sulfonarnide) Sulfanil-(p-anisidide) Metanil-(N-butylanilide) The 1amino-5,8-di(substituted amino)anthraquinone, prepared as describedabove, can then be condensed by known procedures with an acid chloride,such as listed in Table 3, to give the desired dye.

TABLE 3 Acetyl chloride Caproyl chloride Decanoyl chloride Stearylchloride 1- or 2naphthoyl chloride Benzoyl chloride p-t.-Butylbenzoylchloride p-u-Butoxybenzoyl chloride 0-, mor p-Anisyl chloride o-,morbp-Ohlorobeuzoyl chloride mor ptrobenzoyl chloride 0-, mor p-Toluoylchloride 0-, mor p-Brom0benzoyl chloride A second route to the dyesemployed in this invention involves the reaction between an aromaticamine, such as given in Table 2, and a1-acylamino-5,S-dihaloanthraquinone. Aliphatic amines do not readilyundergo biscondensation with these materials. The haloanthraquinone canbe the chloro or bromo derivative, but the chloro compound is preferredfor economic reasons. The reaction is carried out by heating thereactants together in a suitable solvent, such as nitrobenzene,o-dichlorobenzene or an excess of the amine itself. It is advantageousto have an inorganic acid acceptor present, such as an alkali metalacetate, carbonate or a mixture thereof. Copper, a copper salt or amixture thereof can also be added to promote the reaction.

The 1 acylamino-5,8-dichloroanthraquinones can be obtained by acylating1-amino-5,8--dichloroanthraquinone in known fashion with an acidchloride, such as given in Table 3. Alternatively, acylation of thel-amino group can follow the biscondensation reaction with the aromaticamine.

l-amino-5,8-dichloroanthraquinone can be obtained by treatingl-aminoanthraquinone with chlorine in concentrated or fuming sulfuricacid in the presence of a catalyst such as iodine. Such a process iswell known in the prior art. Chlorine is passed through the reactionmixture at about 25-80 C. until the amount of the desired product is ata maximum as shown, for example, by thin layer or vapor phasechromatography. The chlorinated product usually contains, in addition tothe desired product, small amounts of unreacted starting material,monoand trichlorinated compounds, as well as other dichloroisomersPurification of the l-amino-S,S-dichloroanthraquinone is best carriedout after reaction with the acid chloride, by recrystallization from asuitable solvent such as o-dichlorobenzene. The trichlorinated materiall-acylamino- 4,5,8-trichloroanthraquinone is the most diflicult toremove. However, it has been found that minor amounts of this material,up to about 30 Weight percent, in the1-acylamino-5,8-dichloroanthraquinone provide a mixture of dyes uponreaction with the amine, as described above, the properties of whichmixture are comparable to those of the dye obtained from the puredichloro intermediate. In certain cases it has been found that the dyemixture exhibits a crockt'astness, when applied to cellulose-polyesterblend fabrics by the process of Blackwell et al., which is superior tothat obtained when the pure dye is employed. There is, of course, anobvious economic advantage in not having to effect a separation of thedichloro and trichloro intermediates prior to the dye forming step.

Dyes prepared from the aliphatic amines of Table 1 are greenish blue inshade. Those made from the aromatic amines of Table 2, except for themonoazo amines, are green. Monoazo amines produce yellowish greenshades.

Blue dyes employed in this invention can be obtained by the brominationof dyes prepared by the procedures outlined above and derived fromcertain 2-alkyl-, 4-alkyl-, or 2,4dialkylanilines. By such means, forexample, can be obtained dyes having the formula given above wherein Xis NHRg and R is wherein Y is Br or C alkyl and Y is Br or C alkyl,except that Y and Y are not both Br. Such blue dyes may also contain aminor proportion of the 4,5,8- tri(NHR )substituted dye if theunbrominated dye is made from 1-amino-5,8-dichloroanthraquinone with itsattendant impurity of 1-amino-4,5,S-trichloroanthraquinone. Brominationis carried out by adding bromine to a solution or suspension of theintermediate green dye in a suitable organic solvent, such asnitrobenzene or chlorobenzene, and heating the reaction mixture. Such aprocedure is well known in the prior art.

Greenish blue dyes of the formula given above wherein X is NHR and R iswherein R is C alkyl and R is C alkyl or H can be obtained by condensing1,4-diamino-5-nitroanthraquinone with a bromophenyl derivative such as1-bromo-2,4,6- trimethylbenzene, l-bromo 2,4,6 triethylbenzene, 2-bromo-1,3-dimethylbenzene or 2-bromo-l-ethyl-3,5-dimethylbenzene. Thisis carried out as described in the prior art, for example, by heatingthe reactants together in an inert organic solvent in the presence of anacid binding agent, such as an alkali metal carbonate or acetate. Copperor a salt thereof also can be added to accelerate the reaction. Theresulting 1,4-bis(alkylanilino)- S-nitroanthraquinone then can bereduced by known procedures to the S-amino derivative and treated withan acid chloride to give the desired dye.

The cellulosic materials which can be dyed with the dyes employed inthis invention by the previously described Blackwell et al. processinclude all forms of cellulose which increase in size and in flexibilityupon exposure to water. Suitable materials include natural fibers andpurified wood pulps as well as reconstituted cellulose in fiber and filmform. Cotton fibers can be dyed in any of the forms in which they areconventionally used in textile materials and after any of the treatmentsconventionally used to prepare them for dyeing. Also included is cottonwhich has been treated in any way which does not significantly reduceits swelling upon heating with water; raw or scoured cotton and cottonwhich has been mercerized or otherwise preshrunk are dyeable.Reconstituted cellulosic fibers which are sufliciently open in structureso that they are swollen by water and penetrated by a dye solvent aredyeable, for example, cuprammonium rayon. Xanthate viscose rayonnormally has a structure which is more difficult to swell and mayrequire exposure to dye, water, and dye solvent for somewhat longertimes at lower temperatures. To facilitate dyeing, such fabrics can bepretreated with aqueous caustic or the dyeing can be carried out in thepresence of wetting agents, preferably of the nonionic type. Mixtures ofcotton and rayon fibers can be dyed, and the dyes employed herein alsocan be used to dye purified wood pulp and paper. Excluded as the waterswellable cellulosic material, as considered herein, is celluloseacetate which does not exhibit the requisite swellability in thepresence of water.

The synthetic materials which can be dyed with the dyes employed in thisinvention include polyesters, polyamides, cellulose ethers and esters,and copolymers and mixtures thereof with other components intended tomake them more easily dyeable or to add other desirable properties. Manyof the aforesaid dyes can be applied to synthetic materials by aconventional T hermosol dyeing procedure.

The dyes employed in this invention can be applied to water swellablecellulosic materials, or to blends or mixtures thereof with syntheticmaterials, by the abovedescribed Blackwell et al. process. The dyesemployed in this invention are particularly useful for dyeing mixturesand blends of cotton and polyester or polyamide, such as mixturescontaining 50 to 80% polyethylene terephthalate and to 50% cotton. Insuch mixtures, the synthetic material is dyed using conventional processconditions. Since the aforesaid dyes can be used to dye both componentsin a blend or mixture, scourability as a factor in dye selection isavoided since the previously described cross-staini g p l m ha b e m m zThe dyes employed in this invention dye the substrate directly, that is,they do not require oxidation, reduction, hydrolysis, or any otherchemical modification for development of color or fastness. The dyesexhibit excellent fastness to washing, drycleaning and sublimation andgood (fair to excellent) fastness to light.

In dyeing cellulosic materials with the aforesaid dyes using theBlackwell et al. process, water, dye, and dye solvent can be applied tothe substrate in any sequence as long as Water and dye solvent aresimultaneously present at some stage which is either before orsimultaneous with actual dyeing. The preferred method for dyeing fabricscomposed of cellulosic fibers or mixtures of cellulosic and syntheticfibers is to impregnate the fabric with a mixture of one or more dyes,water, and dye solvent in a conventional dye padbath followed bysqueezing to remove excess dye liquor, or to print with asolvent-containing printing paste, and subsequently heating to evaporatesufficient water to effect dissolution of the dye, at which time thefabzric is dyed. Alternatively, water is evaporated, but in aninsufficient amount to effect dissolution of the dye, after whichpressure and heat are applied to effect dissolution without furtherevaporation of water. -Dye pastes can be prepared by conventionaltechniques such as by milling the dye in the presence of a dispersingagent or surfactant. A dyebath can be prepared by diluting the dye pastewith water or with aqueous solvent. Addition of a solvent to the dyepaste before addition of water may cause dye separation and usually isavoided. It will be understood by those skilled in the art thatadditives other than a dye solvent and a dispersing agent can be presentin dyebaths. Such additives frequently include migration inhibitors suchas purified vegetable gums and wetting agents, examples of which areionic and nonionic surfactants such as ethylene oxide condensationproducts, hydrocarbon sulfonates and long-chain alcohol sulfates.Dyebath used in practicing this invention also can contain dyes otherthan those employed in this invention; for example, direct dyes or fiberreactive dyes for cotton or for polyamides can be present for shadingpurposes.

In the preferred dyeing procedure with the dyes employed in thisinvention, an aqueous dye dispersion and the organic solvent are appliedto the fabric from a single padbath. The amount of water in the padbathusually is 70-95 weight percent and the solvent, 5-30 weight percent.The padded fabric is heated at 180-225 C. for 30-180 seconds. Forcotton, temperatures as low as 150 C. usually are adequate. The dyedfabric generally is given an aqueous scour, or an aqueous scour followedby a perchloroethylene scour, to ensure complete removal of surface dye.

The dyes employed in this invention and which cannot be obtained asaqueous dispersions can be employed as solutions in the hot solvent.Alternatively, the dye can be employed as a solution in a low boilingauxiliary solvent, as defined by Blackwell et al., such as a halogenatedhydrocarbon boiling below about 130 C.

The dyes used in the present invention cannot be applied to cotton asvat dyes. At best, a vatting procedure produces a light surface stain onthe cotton fibers which is completely removed by a perchloroethylenescour.

The minimum shade depth of a dyed water swellable cellulosic materialthat is within this invention is defined as having a reflectance colorvalue (8) of at least 2 (using a modification of the reflectance colorvalue S given in British Patent 1,056,358) after the dyed fabric hasbeen scoured in aqueous detergent at -l00 C. and then inperchloroethylene at 50 C.

The reflectance color value is given by the equation where L, M and Nreplace the well known standard 9 colorimetric values X, Y and Z set upby the QIE (Commission Internationale dEclairage). Whereas (where R,=reflectance characteristic of the wavelength; E =radiation function ofthe illuminant, and

5:, i], and 2 =GIE distribution coelficients which characterize aparticular color),

M. Min us. s. an (ii) (where K =dyestutf concentration and F (1R)()2where R), is defined above and r 2(1r) (R -r) residual surfacereflectance of the substrate when dyed completely black).

The sum of (L-l-M-I-N), as the terms are defined in Equation ii, is aconstant for a given dye and independent of the concentration of dye onthe substrate. In order to obtain values for (L+M+N) which areproportional to the shade depth of the dyed fabric, the concentrationterm I/K has been removed from Equation ii; since it is desirable toobtain numbers in the 25 range, the values of the summation (L-l-M-i-N)have been further modified by dividing by 100. This new summation, asused herein and represented by S, is related to S as defined in BritishPatent 1,056,358 by the equation L-i '100 where K is as defined above.

A reflectance color value (S') of 2 represents a light but useful shade,that is, a dyeing rather than a mere staining of the fibers. It has beenfound that such shade depths are easily obtained on cotton with the dyesdescribed herein and, by increasing the concentration of dye in thepadbath, shade depths of several times this figure can be achievedreadily.

The following demonstrates the advantage of using the dyes employed inthe invention in the Blackwell et al. process, as opposed toconventional vatting procedures, in the dyeing of cotton. A piece ofcotton poplin was padded with an aqueous bath containing 50 grams perliter of a 15% aqueous dispersion of the dye of Experiment 1(A). Pickupwas 50-60%. The fabric was dried and then padded with an aqueoussolution containing caustic soda (45 grams per liter) and sodiumhydrosulfite (45 grams per liter). The cloth was steamed for 30 secondsat 104 C. and rinsed. The cotton was then treated for 10 minutes in anaqueous solution of sodium perborate (25 grams per liter) at 49 C. Next,the material was soaped for 5 minutes at 93 C. in a 2% oleate soapsolution, rinsed thoroughly and dried. Finally, the green tintedmaterial was scoured in perchloroethylene at 50 C. for 5 minutes. Almostall of the color was removed from the fabric. In contrast to this asshown below in Example 1, green shades, fast to the perchloroethylenescour, were produced when the dye was applied by the Blackwell et a1.process.

The following demonstrates the non-utility of dyes which arestructurally similar to the dyes employed in the present invention. Thedye l-(p-toluenesulfonamido)- 5,8-bis(p-toluidino)antharaquinone wasprepared by the procedure of Experiment 1(A) except that pyridine wasadded as the acid acceptor and p-toluenesulfonyl chloride was employedas the acid chloride. The dye was applied to cotton broadcloth and to65/35 Dacron polyester/ cotton blend fabric by the procedure ofExample 1. Green shades were produced of good fastness to light andsublimation. However, washfastness was poor unless the dyed fabric wasfirst given a permanent press resin finish.

The following experiments illustrate typical preparative procedures forthe dyes employed in this invention. Parts are given by weight unlessotherwise indicated.

10 EXPERIMENT 1 (A) A mixture of 29.2 parts of1-amino-5,8-dichloroanthraquinone containing a minor amount of l-amino-4,5,8-trichloroanthraquinone, 260 parts of o-dichlorobenzene and 22.3parts of p-nitrobenzyl chloride was stirred under a nitrogen sweep at C.for 2 hours and then allowed to cool to room temperature. The solidswere isolated by filtration, washed successively with methanol, hotwater, 10% aqueous sodium carbonate solution, hot water (until free ofalkali) and finally with methanol, and dried. Yield of1-(p-nitrobenzamido)-5,8-dichloroanthra quinone: 23.3 parts; M.P 28 6298C.

Any of the acid chlorides in Table 3 can be reacted withl-amino-5,S-dichloroanthraquinone by procedures similar to the above toproduce the corresponding l-aroylamino-5,8-dichloroanthraquinone.

A mixture of 218 parts of the aforesaid l-(p-nitrobenzamido) 5,8-dichloroanthraquinone, 214 parts of p-toluidine, 98.4 parts ofanhydrous sodium acetate, 127.2 parts of anhydrous sodium carbonate and2,000 parts of nitrobenzene was stirred at C. for 20 hours. The chargewas allowed to cool to 90 C., whereupon 800 parts of ethanol was added.The mass was allowed to cool to room temperature with stirring and thesolids were isolated by filtration. After washing several times withmethanol and then with hot water, the solids were reslurried in dilutesulfuric acid and isolated by filtration. The dye Was washed with hotwater, until the washings were neutral, and then dried. Yield: 248parts; M.P. 262-265' C. An absorption spectrum of the dye in the visibleregion exhibited a shoulder at 625 mu (a =2'6.8 liters gm.- cm.- and apeak at 665 mu (z= =30.6 liters gm." cm.- Thin layer chromatographyindicated the presence of a minor amount (10- 15 of a yellowish greencomponent in the green product. Based on the above, the main componentis 14pnitrobenzamido)-5,8-bis(p-toluidino)-anthraquinone. The minorcomponent was shown to be l-(p nitrobenzamido)-4,5,8-tris(p-toluidino)anthraquinone by chromatographic comparison withan authentic sample thereof.

(B) A sample of the dye mixture from (A) was recrystallized fromchloroform. Thin layer chromatography indicated the removal of much ofthe 1-(p-nitrobenzamido)-4,5,8-tris(p-toluidino)anthraquinone from themixture, leaving a significantly purer sample of l-(pnitrobenzamido)-5,8-bis (p-toluidino anthraquinone, M.P. 290-291 C. The dye exhibitedabsorptivities of 31.3 liters gm:- cm. at 625 my. (shoulder) and 35.5liters gmr crnr at 664 mg (peak).

EXPERIMENT 2 A mixture of 5 parts of1-(p-nitrobenzamido)-5,8-dichloroanthraquinone, 36 parts ofm-chloroaniline, 2.46 parts of anhydrous sodium acetate and 3.18 partsof anhydrous sodium carbonate was stirred at 190-195 C. under a nitrogenflow for 25 hours. The charge was cooled to 80 C. and 25 parts ofethanol were added. After allowing the reaction mixture to cool to roomtemperature, the solids were isolated by filtration and washed withethanol and then with water. The solids were then reslurried in dilutesulfuric acid, stirred at 80 C. for 1 hour, isolated by filtration,washed successively with water (until free of acid) and finally withethanol, and dried. Yield: 5.5 parts. Thin layer chromatographyindicated a minor amount of a yellowish green impurity in the bluishgreen product. The impurity was shown by chromatographic comparison withan authentic sample to be l-(pnitrobenzamido) 4,5,8tris(m-chloroanilino)anthraquinone. Traces of other impurities wereremoved by extraction with boiling chloroform. The purified dye mixturehad a M.P. of 312-3l6 C. and exhibited absorptivities of 21.1 liters gmrcmr at 612 mu (shoulder) and 24.0 liters gmr cmr at 655 m (peak). Basedon the above procedure and the chromatographic evidence, the mixture 1 1consists of about 85% of 1-(p-nitrobenzamido)-5,8-bis(m-chloroanilino)anthraquinone and about 15% of l-(pnitrobenzamido)4,5,8 tris(m-chloroanilino)anthraquinone.

EXPERIMENT 3 Zinc dust (8.91 parts) was added slowly to a mixture of 34parts of 1,4,S-triaminoanthraquinone, 435 parts of p-n-butylaniline,38.2 parts of boric acid and 48.5 parts of concentrated hydrochloricacid, which mixture was being stirred under nitrogen at 75 C. Thereaction mixture was then heated to 120 C. with stirring for 4 hours,after which it was allowed to cool to below 100 C. Next, 61.2 parts ofpulverized potassium hydroxide were slowly added and the reaction masswas allowed to cool to 65 C. After adding 135 parts of methanol, themixture was stirred overnight and the solids were isolated byfiltration, washed with methanol and then with hot water, until thewashings were neutral, and dried. Yield of1,4-bis(p-nbutylanilino)-5-aminoanthraquinone: 46.5 parts; M.P. 125-131C. Thin layer chromatography (using as eluent a 1:19 mixture ofacetonitrile and benzene) indicated the green product was almost free ofcolored impurities.

A mixture of 45 parts of the above anilinoanthraquinone and 180 parts ofnitrobenzene was heated under a nitrogen purge at 120 C. with stirringfor 30 minutes to remove traces of water from the charge. Next, 16.3parts of p-nitrobenzoyl chloride were added slowly and the mixture wasstirred for 1 hour at 120 C. After cooling the reaction mass to about 90C., 120 parts of ethanol were added and the mixture was allowed to coolwith stirring overnight. The solids were isolated by filtration, washedwith methanol, and then with hot water and finally with methanol, anddried. The green dye product melted at 143146 C. and exhibitedabsorptivities of 28.5 liters gmr' cmf at 624 m (shoulder) and 32.2liters gmr' cmr at 663 mu (peak). Thin layer chromatography(acetonitrile:benzene=1:19) showed the dye to be in a high state ofpurity. Based on the above, the dye is1-(p-nitrobenzamido)-5,8-bis(p-n-butylanilino)anthraquinone.

EXPERIMENT 4 The first part of Experiment 3 was repeated, except thatthe 435 parts of p-n-butylaniline were replaced by 330 parts of mixedxylidines. The yield of product was 41.3 parts; M.P. 154-160" C.

The second part of Experiment 3 was repeated, except that the 45 partsof the anilinoanthraquinone intermediate were replaced by 40 parts ofthe above xylidinoanthraquinone intermediate. The resultingchromatographically pure green dye (43.5 parts) had a M.P. of 204-207 C.and exhibited absorptivities of 29.3 liters gmr cmr' at 620 m (shoulder)and 33.4 liters gm.-' cm.- at 655 m (peak). Based on the above, the dyeis 1-(p-nitrobenzamido)-5,8-bis(xylidino)anthraquinone.

EXPERIMENT 5 A mixture of 25.5 parts of S-aminoquinizarin, 4 parts ofcaustic soda, 120 parts of isopropanol and 50 parts of water was heatedto the reflux temperature under nitrogen. Next 17.4 parts of sodiumhydrosulfite were added and the reaction mixture was stirred at refluxfor /2 hour, after which 99.2 parts of cyclohexylamine were added andthe mixture was stirred at the boil for 19 hours. The nitrogen purge wasdiscontinued and the charge was treated with 2.25 parts of sodiumm-nitrobenzene-sulfonate and stirred in air at the reflux temperaturefor 1 hour. After the charge had cooled to room temperature, the solidswere isolated by filtration, washed successively with isopropanol, hotwater, until the washings were neutral, and isopropanol, and dried.Yield of 1,4-bis(cyclohexylamino)-5-aminoanthraquinone: 34.0 parts; M.P.215- 218 C. Thin layer chromatography indicated small amounts of coloredimpurities in the blue product,

A solution of 4.46 parts of p-nitrobenzoyl chloride in 40 parts ofnitrobenzene was added in portions to a mixture of 8 parts of the above1,4-bis(cyclohexylamino)-5- aminoanthraquinone in 60 parts ofnitrobenzene which was being stirred under nitrogen at 100 C. Afterstirring for 1 hour, the reaction mixture was cooled to C. and treatedwith 32 parts of ethanol. After the reaction mass had cooled to roomtemperature, the solids were isolated by filtration, washed withisopropanol and then with hot water, until the washings were neutral,and dried. Yield: 7.5 parts; M.P. 248-253 C. After recrystallizationfrom chloroform/isopropanol, the chromatographically pure, greenish bluedye had a M.P. of 260-262 C. and exhibited absorptivities of 37.4 litersgmr cmr at 608 m and 51.3 liters gmr' cm. at 658 my. Based on the above,the dye is 1-(p-nitrobenzamido)-5,8-bis(cyclohexylamino anthraquinone.

EXPERIMENTS 6-9 Additional green dyes employed in this invention wereprepared by procedures analogous to those described in Experiment 1(A).In each case, benzoyl chloride was employed in place of p-nitrobenzoylchloride so as to yield l-benzamido-5,8-diarylaminoanthraquinones. Thefollowing table shows the properties of the dyes produced. In the table,X represents the 5- and 8-substituents. In ecah experiment, the crudedye product contained 10-15% of the 4,5,8-tris(X)substituted compound.The minor component was removed by recrystallizing the crude product asdescribed in Experiment 1(B). The amount of the minor component wasjudged by thin layer chromatography and in each case its structure wasverified by chromatographic comparison with an authentic sample of the4,5,8-triarylaminoanthraquinone. The contaminants were found to beyellower and tinctorially weaker than the main product.

1 Shoulder.

EXPERIMENT 10 A procedure analogous to that described in Experiment 3was used to prepare 1-benzamido-5,8-bis(cyclohexylamino)anthraquinone.The pure greenish blue dye exhibited the same melting point and spectralcharacteristics as the dye of Experiment 5.

EXPERIMENT 11 A procedure analogous to that described in Experiment 3was used to prepare1-(p-chlorobenzamido)-5,8-bis(ptoluidino)-anthraquinone. The pure greendye had a M.P. of 276-278 C. and exhibited absorptivities of 32.1 litersgm.- cm." at 620 III/L (shoulder) and 36.3 liters gm.- cm. at 661 mu(peak).

The following examples illustrate the preparation of the dyed fibers ofthis invention. When the green dyes of Experiments 1-4 and the greenishblue dye of Experiment 5 were used to dye cotton or polyester/cottonblend fabrics by the procedures of Examples 1 and 2, excellent light,wash and sublimation fastness were achieved. The fastness to crockingwith the dye of Experiment 1(B) was slightly inferior to that with thedye of Experiment 1(A). Similarly, the green dyes of Experiments 6-9 and11 and the greenish blue dye of Experiment 10 provided excellentfastness to washing, drycleaning and sublimatio a d f ir to good fas eto igh 13 EXAMPLE 1 Dyeing 65/35 Dacron polyester/cotton blend fabric(A) A padbath was prepared from:

Grams An aqueous green dye paste (15% active ingredi- A continuouslength of 65/35 Dacron polyester/cotton fabric was padded at 60% uptake,based on the weight of the fiber, and the padded fabric was passed at arate of 2 yards per minute between two 1,000-watt infrared lamps(Fostoria-Fannon, Inc., Infrared Heater Model 6624), with each lampshining on opposite surfaces of the fabric from a distance of about 3inches. The continuously-moving fabric was passed through a circulatingair oven at 80100 C., with a hold-up time of one minute, and thenthrough an oven at 200-210 C. with a holdup time of 1.7 minutes. The hotdry fabric was cooled to room temperature and rinsed for one minute eachin sequence: in water at 2030 C., in water at 90-95 C., at 9095 C. inwater containing 1% of an ether-alcohol sulfate detergent, in water at9095 C., and in water at 20-30 C. The material was dried, then scouredfor 5 minutes in perchloroethylene at 50 C., and dried again. The fabricwas uniformly colored (deep green) in a satisfactory union dyeing of thecotton and Dacron fibers.

(B) Part A was repeated except that the heating was carried out asfollows. The padded fabric was passed at a rate of 2 yards per minutebetween banks of infrared lamps, with one 1,000 watt lamp(Fostoria-Fannon, Inc., Infrared Heater Model 6624) shining on eachsurface perpendicular to the fabric from a distance of about 3 inches.The moist fabric was then passed over a series of four revolvingsmooth-surfaced drums increasing stepwise in temperature from 100 C. toabout 150 C. The average contact time on each drum was about 18 seconds.Next, the fabric moved continuously into an oven held at about 210 C.where the total contact time was about 90 seconds.

EXAMPLE 2 Dyeing cotton broadcloth Example 1A was repeated except that a100% mercerized cotton broadcloth was employed, the amount of glycol,Carbitol and boric acid each was increased 50%, and The cotton cloth wasdyed a deep, uniform green shade. the maximum temperature was reduced toabout 180 C. After the material was scoured in aqueous detergent, thenin perchloroethylene at 50 C. for 5 minutes, and dried, as describedabove, it exhibited a reflectance color value EXAMPLES 3-5 When Example2 was repeated, using the dyes of Experiments 1(B), 5 and 10, instead ofthe dye of Experiment 1(A), the dyed fabrics exhibited reflectance colorvalues of 6.57, 4.30 and 4.57, respectively.

EXAMPLE 6 Printing of 100% cotton fabric A cotton fabric was padded toabout 70% pickup with an aqueous solution containing 200 grams per literof polyethylene glycol (M.W. 350). The padded fabric was heated at 160C. for 5 minutes to evaporate water. The fabric was then printed in apattern with a print paste prepared from:

Grams An aqueous green paste (15% active ingredient) containing the dyeof Experiment 2 l0 Purified natural gum ether thickener 60 Water 30 Theprinted fabric was heated at 180 C. for seconds, scoured in watercontaining an ether-alcohol sulfate detergent at about 90 C. for 5minutes, dried, scoured in tetrachloroethylene at about 50 C. for 5minutes and dried. The printed areas were strongly dyed.

EXAMPLE 7 Printing of 65/35 Dacron polyester/ cotton blend fabricExample 6 was repeated except that a 65/35 Dacron polyester/cottonfabric was employed, the glycol was reduced to grams per liter, and themaximum temperature was increased to 200 C. The fastness results of theprints obtained were comparable to those of fabric dyed with the samedye by the procedure of Example 1.

The embodiments of the invention in which an exclufive property orprivilege is claimed are defined as folows:

1. Uniformly dyed blue to green water swellable cellulosic fibers, saidfibers being fast to washing, drycleaning and sublimation and exhibitinga reflectance color value (S) after scour of at least 2, said dyedfibers being produced by contacting water swellable cellulosic fiberssequentially or concomitantly with water, ethylene glycol or aderivative thereof and, while the fibers are still swollen, theessentially Water insoluble, non-vattable anthraquinone dye having theformula wherein R is C alkyl, naphthyl, phenyl or phenyl substitutedwith C alkyl, C alkoxy, Cl, Br, CF or N0 and X contains 6-18 carbonatoms and is NHalkyl, NHcyclohexyl, N(alkyl) or NHR wherein R is 0wherein a is H, alkyl or alkoxy, b is H, alkyl, alkoxy, F, Cl, Br,NHCOalkyl or NHCOR, and c is H, alkyl, alkoxy, F, Cl, Br, NHCOalkyl,NHCOR, R, OR, NHR, CB CN, CONH CONalkyl, CON(alkyl) CONHR, CON(alkyl)R,SO NH sO NHalkyl, SO NHR, SO N(alkyl) SO N(alkyl)R, COalkyl, COR, COalkyl, CO R, SOgalkyl, SO R or N=NR, wherein R is phenyl or phenylsubstituted with alkyl, alkoxy, halogen, CR, 01' N02 provided that the6-position of R is substituted with H, or if the 2-position issubstituted with Br or alkyl of greaer than two carbon atoms, then H orBr, or if the 2-position is substituted with C alkyl, then H, Br or Calkyl. 2. The fibers of claim 1 wherein the dye is l-(p-nitrobenzamido-5,8-bis (p-toluidino) anthraquinone.

, 3. The fibers of claim 2 wherein the dye contains up to 30%l-(p-nitrobenzamido)-4,S-8-tris(p-toluidino)anthraquinone.

4. The fibers of claim 1 wherein the dye isl-(p-nitrobenzamido)-S,8-bis(p-n-butylanilino)anthraquinone.

5. The fibers of claim 1 wherein the dye isl-(p-nitrobenzamido)-5,8-bis(xylidino)anthraquinone.

6. The fibers of claim 1 wherein the dye is l-(p-nitrobenzamido -5,8-bis(cyclohexylamino) anthraquinone.

7. The fibers of claim 1 wherein the dye isl-benzamido-5,8-'bis(cyclohexylamino)anthraquinone.

8. The fibers of claim 1 wherein the fibers are cotton fibers.

9. The fibers of claim 1 admixed or blended with synthetic fibers.

10. The fibers of claim 9 wherein the synthetic fibers are polyesterfibers.

l 6 References Cited UNITED STATES PATENTS 2,339,913 1/1944 Hanford 81203,473,882 10/1969 Weber et al 8--39 FOREIGN PATENTS 585,798 2/ 1947Great Britain. 1,147,110 4/1969 Great Britain. 1,071,074 6/ 1967 GreatBritain. 1,217,380 12/ 1970 Great Britain.

GEORGE F. LESMES, Primary Examiner P. C. IVES, Assistant Examiner US.'Cl. X.R.

